NIRT: Nanoscale Processes in the Environment: Nanobiogeochemistry of Microbe/Mineral Interactions

EAR-0103053Hochella这项研究计划的主要目标是在纳米(10-9米)尺度上观察和定量描述微生物(特别是细菌)和矿物之间发生的复杂相互作用。这些相互作用在地球表面附近的土壤和岩石中普遍存在。我们假设，当直接在纳米尺度上研究微生物-矿物相互作用时，将导致相对于当前试图解释矿物-微生物关联和依赖的概念和模型的外来行为的发现。为了实现我们的目标，我们将在很大程度上依赖于生物力显微镜(BFM)，这是我们在过去两年里在实验室开发的原子力显微镜的变体。这项技术首次允许直接测量全功能细胞和任何其他衬底之间的力(吸引力/排斥力和粘附力)作为分离距离的函数。细菌和矿物表面之间的可重复和可靠的测量很容易以纳米到皮克(10-12)牛顿力的分辨率获得，同时控制它们的分离到纳米级。这给了我们一个前所未有的视角，了解作为水化学、微生物生理学和表面矿物学功能的矿物-微生物相互作用的错综复杂。这项工作的实际应用包括开发新一代表面或地下环境中微生物的传输模型，利用从我们的BFM和相关测量获得的丰富的纳米级信息。这样的模型在未来开发更强大的地下生物修复战略方面应该非常有用。这项提案是应“纳米科学与工程”(NSF 00-119)的征集而提交的。

EAR-0103053HochellaThe primary objective of this research program is to observe and quantitatively characterize, on the nanometer (10-9 meters) scale, the complex interactions that occur between microorganisms (specifically bacteria) and minerals. These interactions are ubiquitous in soils and rocks near the Earth's surface. We hypothesize that microbe-mineral interactions, when studied directly at the nanoscale, will result in the discovery of exotic behavior relative to current concepts and models that seek to explain mineral-microbe association and dependence. In order to accomplish our goal, we will depend heavily on biological force microscopy (BFM), a variation of the atomic force microscope that we have developed in our lab over the last two years. This technique, for the first time, allows for the direct measurement of forces (both attractive/repulsive and adhesive) between fully functional cells and any other substrate as a function of separation distance. Reproducible and reliable measurements between bacteria and mineral surfaces are readily obtained with nano- to pico (10-12)-Newton force resolution while at the same time controlling their separation to the nanometer level. This has already given us an unprecedented view of the intricacies on mineral-microbe interaction as a function of water chemistry, microbial physiology, and surface mineralogy. Practical application of this work includes the development of a new generation of transport model for microorganisms in surface or subsurface environments, using the wealth of nanoscale information obtained from our BFM and associated measurements. Such models should be very useful in developing more robust subsurface bioremediation strategies in the future. This proposal was submitted in response to the solicitation "Nanoscale Science and Engineering" (NSF 00-119).